Welding guns for application of a weld to a desired site generally are provided at the remote end of a conduit in which is located a continuous weld wire extending from a wire source and a power cable extending from a power source. Often such welding guns are of the vacuum type which permit undesirable fumes and smoke to be removed from the welding site through the conduit.
Traditionally, this conduit has been of corrugated construction along the whole length thereof, both such structure provides no support for the weld wire or power cable and can wear through to expose the electrical power cable.
In my U.S. Pat. No. 4,496,823, the disclosure of which is incorporated herein by reference, there is described a novel multipassage flexible smooth-surfaced conduit which overcomes the problems of the prior art. In some instances, however, the conduit of my U.S. Pat. No. 4,406,823 is not sufficiently flexible to permit the ideal maneuverability of the welding gun head to make welds, particularly in hard-to-get-at locations.
For this reason, I invented a bellows-like flexible connector to connect the smooth-surfaced conduit to the welding gun head to permit the welding gun to be turned about universally with respect to the conduit. That structure forms the subject of my U.S. patent application Ser. No. 307,921 filed Feb. 9, 1989, the disclosure of which is incorporated herein by reference.
It has been found that, in the use of welding guns provided with such a bellows connector, it sometimes occurs that the upstream tubular fibrous or plastic end of the welding gun handle abrades the power cable at that location, with the potential for exposing the cable wire and causing a short circuit.